The Neurological Research Center (Epilepsy) at Yale is organized as a widely based investigative effort into mechanisms of epileptic seizures and their control, and of biological phenomena associated with seizures, with the aim of discerning factors responsible for the occurrence, frequency and nature of seizure disorders. Both experimental and clinical studies are oriented towards development of physiological and metabolic-biochemical-pharmacological methods effective for treatment and control of epileptic seizures. The investigations include physiological, chemical and structural correlates of neuronal and cerebral excitability changes: studies of epileptogenesis in identified invertebrate neuronal systems (using convulsant and anticonvulsant drugs and specific ions), mechanisms of action of anticonvulsant drugs involving synaptic transmission, calcium and neurotransmitter release, cerebral protein endogenous phosphorylation (enzymes, role of calcium, effects of anticonvulsant drugs and other agents) in relation to membrane changes and epileptic seizures, experimental studies of effects of convulsant and anticonvulsant drugs on cerebral sensory evoked responses and seizure activity, controlled clinical studies of anticonvulsant drugs, with pharmacokinetics (i.e., dip opylacetate, eterobarb), and menstrual cycles on seizure activity (correlating serum levels, EEG power spectra and neuropsychological functions), investigations of cerebral sensory evoked potentials in epileptic patients to determine the frequency, specificity and significance of a recently found potential wave change in complex partial (focal) epilepsy, and a highly controlled investigation and evaluation of "feedback" or operant conditioning of specific EEG rhythms and its possible role in the effective reduction and long-term control of epileptic seizures in man.